Insulating-sheet.



G. S. BIRD.

INSULATING SHEET.

APPLICATION FILED 133.14, 1910.

Patented Aug. 8, 1911.

a HM i'iineaaesx' live/670207 5 4mm Q. 9; M

pheric temperature.

' "UNITED srrns P:

CHARLES S. BIRD, OF EAST WALPOLE, MASSACHUSETTS.

INSIlLATING-SHEET.

Specification of Letters Patent.

Patented Aug. 8, 1911.

Application filed February 14, 1910. Serial No. 543,838.

for use in refrigerator cars or other refrigk crating structures inwhich the tem erature 1s conslderably below the norma atmos- The objectof the invention is to so construct a paper insulating sheet orstructure having a multiplicity of air cells that the paper sheet havinsaid air cells shall be protected from molsture. i

The invention consists in the peculiar insulating sheet herein shown anddescribed.

Figure 1, represents a plan view of a portion of a sheet of the newinsulating material. .Fig. 2, represents an enlarged sec-- tional viewtaken on lines 2-2, Figs. 1 and 3. Fig. 3, represents an enlargedsectional view taken on lines.33, Figs. 1 and 2.

Similar numbers of reference designate corresponding parts throughout.

Insulating sheets or strips of the nature herein referred to are formedof paper and are used for the general purposes of'insulating chambers orcompartments from the heat of the atmosphere. Said sheets may, however,be used ,to advantage as non-conductors of heat in or on any suitablestructure.

In refrigerating cars or compartments the temperature is considerablyless than that of the atmosphere and, consequently, the

Walls of said compartment become heated sufficiently to effect thecondensation of moisture contained in the cooler air within thecompartment. Such moisture attacks and, ultimately, will injuriouslyaffect ordi nary paper insulation and particularly such insulationhaving air cells formed therein.

In carrying this invention into practice, I find that a satisfactoryinsulation may be formed by a compound structure formed by severallayers of paper, one of which is furnished with'means for segregating amulti- 'plicity of'small bodies of air, and others of which 'form coverseach common to all of the aircells. at one side of the cellular sheet,but such insulation in actual use attracts moistii're and the fibrouspaper material absorbs such moisture and soon becomes pulpy and useless;tearing or falling away from its su'pportiugmeans arid leaving openingsfor heated air. v

AsshoWn in the drawings 5, represents the. cellular paper sheet havingat each side a multiplicity of air cells 6, 6, formed by indenting orembossing said sheet: 7 7, are

outer sheets of waterproof paper which are secured to the ridges orboundaries of the .air cells 6, 6, by the comparatively thick coatingsof asphaltic waterproof adhesive 8, 8, in which said ridges arepartially embedded, said coatings 8, 8, being applied to the surfaces ofthe sheets 7 7 beforesaid sheets are brought-against the sheet 5.

' In insulation of, this character one object is to secure theinsulating qualities of air by fur ishing means for segregatingcomparatively small bodies thereof, to avoid the circulation of the air.The more complete the layer of air surrounding the compartment to beinsulated the more effective is the insulation and, therefore, the shapeof the air cells 6, 6, is preferably such that the edges of the aircells at one side of .the sheet 5 overla the similar cells 6, 6, at theother side 0 said sheet so that, in effect, as to its insulatingproperties, the sheet 5 forms continuous unbroken means for segregatingsmall bodies of air without breaking the continuity 0f the layer of air,while the waterproof covers 7, 7, with their asphaltic layers 8, 8,protect the sheet 5 from moisture.

Having thus described my invention I claim as new and desire to secureby Letters Patent. I

An insulating sheet comprising a bodyportion formed of a sheet of paperprovided on each side with rows of indentations to constitute cells, anda row of rid es between each pair of rows of cells, t e cells portion, asheet of paper positioned against outer sheets, said rows of ridgesembedded the otherf side of said body to 0105; the in said coating.

mouths 0 the other cells, the edges 0 said 1 -1 cells upon one side ofthe body-portion over- CHARLEb BIRD lapping the edges of the cellsuponthe other Witnesses:

side, and a heavy coating of asphaltio mate- E. L. FLEMING,

rial upon the inner faces of each .of said ELMER H. BARTLETT.

